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What is this Number?

N is a number where each digit is divisible by its place, for example: 1527 1 has to be divisible by 1, 5 divisible by 2, 2 divisible by 3, and 7 divisible by 4. Additionally, N must be divisible ...
404 views

Chess Pawn Capture Game!

Say there's an 8x8 board with the far ends completely occupied by pawns (White: a1 b1 c1 d1 e1 f1 g1 h1, Black: a8 b8 c8 d8 e8 f8 g8 h8). The aim of this game is to capture all but 1 pawn using the ...
1k views

Can you find my friends' birthday

A friend of mine has an interesting birthday. If you shorten the date month and year and use UK date format, it reads the year in full, his birthday falls on a Friday. When he is as old as the year ...
1k views

How Many Times will 1 Appear on the Broken Clock?

You just got a new clock, but it's broken. Your friend tells you he can fix it, but he needs a little bit of data from it. One thing he needs is how many times 1 appears in the run of 2 days. The ...
6k views

Splitting a Plate into 4 Equal Pieces

You are stuck on an island and have been tasked by the natives with dividing a plate of chocolate into 4 equal pieces, one for each of the island's gods. Each god must have an equal share, or you go ...
529 views

A Hunter wants to get on a Bus [duplicate]

A hunter wants to get on a bus, but belongings which have larger than 1 meter dimensions is not allowed. So how will he be able to get his rifle (which is 1.5 meters) together with him without ...
2k views

Banana? Or Orange?

25 kids were in a class, they were all trading lunches. Each kid traded their lunch 5 times. At first 12 kids had bananas. At first 13 kids had oranges 16 kids like bananas 14 kids like oranges In ...
475 views

From Knights to Kings on a rectangle

In From knights to kings, we were asked On a NxN chess board $N^2$ knights are placed (one per cell). Each pair of knights, who control each other (i.e. one move away from each other) are friends. ...
1k views

Is it Always Possible? Colour Flipping

There's a 4x4 square, where switches are either red or green. When you flip a switch, all the buttons on that row and column will change color. Is every starting position possible to complete? If not ...
963 views

16 Buttons, Turn them all Red or Green?

There's 16 buttons arranged in a 4 by 4 square. They are coloured either red, or green. They appear like this (red being 1, green being 0) 1010 0101 1100 0011 Each press will switch all the ...
400 views

Abalone Migration

Abalone is a 2-player board game. Here's a brief explanation from Wikipedia: The board consists of 61 circular spaces arranged in a hexagon, five on a side. Each player has 14 marbles that rest in ...
2k views

A puzzle of trust and lies, allies and spies

Here is a puzzle involving distrust and asymmetric knowledge. (It was inspired by, but not exactly following, the board game The Resistance: Avalon.) There are ten resistance fighters trying to ...
3k views

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Water glass and wine glass [duplicate]

You have two equal glasses. One is filled with water. One is filled with wine. Now you take a spoonful from the water glass, put it into the wine glass, and stir until it is well mixed. Then you take ...
5k views

Poisoned Bottle of Wine! [duplicate]

This puzzle is taken directly from a site and reworded. The site can be found at the bottom of this question. You are king of an empire and you are going to have a party soon. The party is the most ...
12k views

7 Trees, 6 Rows, 3 Per Row?

Can you arrange 7 trees so that there are 6 rows of 3 trees? It is entirely possible. Note: A tree can be part of more then one row, for example a if you arranged a 3x3 square (9 trees) the tree in ...
16k views

Is the Glass Half Full with water?

You, a right cylinder glass of water, 3 buttons, instructions, and a large flat land that seems to go on forever, are the only things that exist in a universe. In this weird universe, the exact same ...
370 views

Dominoes on a Chess Board [duplicate]

Imagine an 8x8 chessboard has two opposite corners taken out, with 62 squares left over. Is it possible to lay 31 dominoes with the size 2x1 so they cover all of the empty, left over, squares?
6k views

Can you Turn MI to MU?

Using the letters M, I, and U, which can be used to create words. Can you turn MI into MU using in each step one of the following rules: Insert a U to the end of a word ending in I. e.g: MI becomes ...
10k views

How many paths are there through a chess board? [closed]

A pawn is placed on the lower left corner square of a standard 8 by 8 chessboard. A 'move' involves moving the pawn, where possible, either: one square to the right, one square up, or diagonally one ...
2k views

Directions on an infinite compass rose

An old sailor, by the name of John, was in his attic with his bright young great-nephew Stewart, showing him all the old tools they used to use while at sea. Stewart was fascinated by all the ...
327 views

Largest No-Capture Setup?

Think of a Chinese Game Board, and how you can make jumps. Now think of actual checkers where you capture pieces. How many marbles can you place without a capture possible? There's one slight rule to ...
775 views

Scott is an expert outdoorsman, pursuing his dream by living in the remote Alaskan wilderness. Scott has everything he needs, and would prefer to remain a recluse, yet he will have to leave his home ...
6k views

How do I arrange pencils so they all touch each other?

How do you arrange 6 pencils so that each one touches the other five? And what about 7 or 8?
1k views

Are you a Detective

A detective friend of yours was trying to find clues for a crime he was investigating, he was almost done but a concluding location will help you close the case. Unfortunately your friend could only ...
4k views

The Dragon or the Magnifying Glass?

You've been sent to prison, but the prisons where you are from are very clever. They do not just lock you up, they put you in a room with 2 doors. Door A is guarded by an evil dragon that will kill ...
976 views

Social Engineering (The Birthrate Problem)

The distant country of Toomalia has a birthrate of 67 boys for every 33 girls. In an effort to restore a 50:50 gender ratio in the country, Toomalian policymakers institute a mandatory new social ...
2k views

A Drawer of Socks

Bob wakes up one morning, and he needs to grab a pair of socks for work. In his sock drawer, he has 5 pairs of blue socks, 3 pairs of red socks, and 4 pairs of white socks (Bob is American and very ...
2k views

How do we get those dang Illuminati?

The Illuminati just stole our office They shot JFK and have committed numerous crimes against humanity (not really) but we usually let that slide. But for stealing our offices, we have decided to ...
2k views

The Illuminati and the Knights Templar

Some people in the American Senate are working for secret organizations. Some work for the Illuminati, some work for the Knights Templar, and some work for both. The are also innocent citizens who are ...
904 views

The generous team puzzle

An intelligent team, ‘Smarty Pants’, applying to a competition completes an evaluation form early. Since they are feeling generous they randomly spread their assignment to all 10 teams applying from ...
1k views

The way to Acarien, with Knights and Knaves

Once again, you're on your way to Acarien. You find yourself in a land of Knights and Knaves, who understand your language but don't speak it. You understand nor speak their language, but you do know ...
3k views

Are you Really Smart

The government has introduced a standardised test to identify dumb people and make them ineligible to apply for any government jobs, a pass in the exam is mandatory for applications in future. It ...
2k views

The way to Acarien puzzle

You are on a quest to the find the lost kingdom of Acarien. On your way, you end up at a fork in the road. Both paths look exactly the same. At the junction sits a wise man. The wise man will only ...
20k views

A double-agent with a conundrum

You are a double-agent in the most important war of the 20th century, The Falklands war. For years you have been playing the United Kingdom and Argentinian governments against each other, taking ...
1k views

Crack the Code #4

The park bench has been compromised as a safe location, so you decide to meet in the lobby of the nearest hotel. Again, the envelopes are traded securely, along with the money you are receiving for ...
945 views

Crack the Code #3

You return to the bench after cracking the last code, and you notice an envelope on the ground directly under it. You put down your envelope with the previous code and pick up the new one, ...